So while I'm catching up on things here, I'll pose a question I'm not sure I've seen answered here...

Most roof / rack top transportation of these large kayaks seems to be flat (bottom down). However this obviously uses up a lot of the horizontal rack real estate. If we wanted to transport three or four kayaks (not necessarily all AI or TI), would there be an issue with using a more vertical (on side) method (like a fixed "J" mount)?